Hello…i just bought NodeMCU and try to use Blynk to monitor something.
I begin to try the simple code following the video on Blynk site tutorial to control LED embedded on NodeMCU through Blynk app. Yet, the blynk unable to connect to nodemcu.
here is the code:

The normal way to use Blynk is to have a device, that is connected to your home Wi-Fi network, then allow your phone to connect to the internet either via your home Wi-Fi, mobile data, or a different Wi-Fi system (say when you’re at work, or when you’re using a public hotspot.

The NodeMCU uses the home network to talk to the Blynk server, and the phone uses whatever internet connection is available to talk to the Blynk server. The phone and NodeMCU never talk directly by Wi-Fi, it’s always done via the Blynk server.

This means that you’d normally put your home Wi-Fi SSID and password into the code, along with your Blynk Auth code, and upload it to the NodeMCU.

If you don’t have a home Wi-Fi network then it may be possible to use a mobile hotspot that you’ve set-up on your phone, but often this won’t work because the mobile network provider blocks the Blynk protocol when sharing the internet connection via a hotspot.